Blimp-1 inhibits the control of parasite growth during experimental visceral leishmaniasis.

<p><i>Prdm1</i>^fl/fl and <i>Prdm1</i>^ΔT C57BL/6 mice were infected with <i>L</i>. <i>donovani</i> and spleen (<b>A</b>) and liver (<b>D</b>) parasite burdens were measured at times indicated. The frequency of Th1 and Tr1 cells in the spleen (<b>B</b>) and liver (<b>E)</b> were measured by flow cytometry. Organ weights and frequencies of TNF producing CD4⁺ T cells in the spleen (<b>C</b>) and liver (<b>F)</b> were also assessed, as were serum TNF and IFNγ levels (<b>G</b>). Antigen-specific Th1 cell frequency (<b>H</b>), IFNγ, TNF and IL-10 production (<b>I</b>) were measured in splenocytes after 24 hours of culture in the presence of parasite antigen at times indicated. In all panels, closed shapes represent <i>Prdm1</i>^fl/fl mice, while open shapes indicate <i>Prdm1</i>^ΔT littermates. Representative of 5 similar experiments, mean ±SEM, n = 5–6 in each group in each experiment, **p<0.01, *p<0.05, Mann-Whitney U test.